Too good to treat? ischemic stroke patients with small computed tomography perfusion lesions may not benefit from thrombolysis

Objective

Although commonly used in clinical practice, there remains much uncertainty about whether perfusion computed tomography (CTP) should be used to select stroke patients for acute reperfusion therapy. In this study, we tested the hypothesis that a small acute perfusion lesion predicts good clinical outcome regardless of thrombolysis administration.

Methods

We used a prospectively collected cohort of acute ischemic stroke patients being assessed for treatment with IV-alteplase, who had CTP before a treatment decision. Volumetric CTP was retrospectively analyded to identify patients with a small perfusion lesion (<15ml in volume). The primary analysis was excellent 3-month outcome in patients with a small perfusion lesion who were treated with alteplase compared to those who were not treated.

Results

Of 1526 patients, 366 had a perfusion lesion <15ml and were clinically eligible for alteplase (212 being treated and 154 not treated). Median acute National Institutes of Health Stroke Scale score was 8 in each group. Of the 366 patients with a small perfusion lesion, 227 (62%) were modified Rankin Scale (mRS) 0 to 1 at day 90. Alteplase-treated patients were less likely to achieve 90-day mRS 0 to 1 (57%) than untreated patients (69%; relative risk [RR] = 0.83; 95% confidence interval [CI], 0.71–0.97; p = 0.022) and did not have different rates of mRS 0 to 2 (72% treated patients vs 77% untreated; RR, 0.93; 95% CI, 0.82–1.95; p = 0.23).

Interpretation

This large observational cohort suggests that a portion of ischemic stroke patients clinically eligible for alteplase therapy with a small perfusion lesion have a good natural history and may not benefit from treatment. 

Ann Neurol 2016

Auto-antibodies to contactin-associated protein 1 (Caspr) in two patients with painful inflammatory neuropathy

Auto-antibodies against the paranodal proteins neurofascin-155 and contactin-1 have recently been described in patients with chronic inflammatory demyelinating polyradiculoneuropathy and are associated with a distinct clinical phenotype and response to treatment. Contactin-associated protein 1 (Caspr, encoded by CNTNAP1) is a paranodal protein that is attached to neurofascin-155 and contactin-1 (CNTN1) but has not yet been identified as a sole antigen in patients with inflammatory neuropathies. In the present study, we screened a cohort of 35 patients with chronic inflammatory demyelinating polyradiculoneuropathy (age range 20–80, 10 female, 25 male) and 22 patients with Guillain-Barré syndrome (age range 17–86, eight female, 14 male) for autoantibodies against paranodal antigens. We identified two patients, one with chronic inflammatory demyelinating polyradiculoneuropathy and one with Guillain-Barré syndrome, with autoantibodies against Caspr by binding assays using Caspr transfected human embryonic kidney cells and murine teased fibres. IgG3 was the predominant autoantibody subclass in the patient with Guillain-Barré syndrome, IgG4 was predominant in the patient with chronic inflammatory demyelinating polyradiculoneuropathy. Accordingly, complement deposition after binding to HEK293 cells was detectable in the patient with IgG3 autoantibodies only, not in the patient with IgG4. Severe disruption of the paranodal and nodal architecture was detectable in teased fibres of the sural nerve biopsy and in dermal myelinated fibres, supporting the notion of the paranodes being the site of pathology. Deposition of IgG at the paranodes was detected in teased fibre preparations of the sural nerve, further supporting the pathogenicity of anti-Caspr autoantibodies. Pain was one of the predominant findings in both patients, possibly reflected by binding of patients’ IgG to TRPV1 immunoreactive dorsal root ganglia neurons. Our results demonstrate that the paranodal protein Caspr constitutes a new antigen that leads to autoantibody generation as part of the novel entity of neuropathies associated with autoantibodies against paranodal proteins.

Brain 2016

Evaluation of Tau Imaging in Staging Alzheimer Disease and Revealing Interactions Between β-Amyloid and Tauopathy

Importance  In vivo tau imaging may become a diagnostic marker for Alzheimer disease (AD) and provides insights into the pathophysiology of AD.

Objective  To evaluate the usefulness of [18F]-AV-1451 positron emission tomography (PET) imaging to stage AD and assess the associations among β-amyloid (Aβ), tau, and volume loss.

Design, Setting, and Participants  An imaging study conducted at Knight Alzheimer Disease Research Center at Washington University in St Louis, Missouri. A total of 59 participants who were cognitively normal (CN) (Clinical Dementia Rating [CDR] score, 0) or had AD dementia (CDR score, >0) were included.

Main Outcomes and Measures  Standardized uptake value ratio (SUVR) of [18F]-AV-1451 in the hippocampus and a priori–defined AD cortical signature regions, cerebrospinal fluid Aβ42, hippocampal volume, and AD signature cortical thickness.

Results  Of the 59 participants, 38 (64%) were male; mean (SD) age was 74 (6) years. The [18F]-AV-1451 SUVR in the hippocampus and AD cortical signature regions distinguished AD from CN participants (area under the receiver operating characteristic curve range [95% CI], 0.89 [0.73-1.00] to 0.98 [0.92-1.00]). An [18F]-AV-1451 SUVR cutoff value of 1.19 (sensitivity, 100%; specificity, 86%) from AD cortical signature regions best separated cerebrospinal fluid Aβ42-positive (Aβ+) AD from cerebrospinal fluid Aβ42-negative (Aβ−) CN participants. This same cutoff also divided Aβ+ CN participants into low vs high tau groups. Moreover, the presence of Aβ+ was associated with an elevated [18F]-AV-1451 SUVR in AD cortical signature regions (Aβ+ participants: mean [SD], 1.3 [0.3]; Aβ− participants: 1.1 [0.1]; F = 4.3, P = .04) but not in the hippocampus. The presence of Aβ+ alone was not related to hippocampal volume or AD signature cortical thickness. An elevated [18F]-AV-1451 SUVR was associated with volumetric loss in both the hippocampus and AD cortical signature regions. The observed [18F]-AV-1451 SUVR volumetric association was modified by Aβ status in the hippocampus but not in AD cortical signature regions. An inverse association between hippocampal [18F]-AV-1451 SUVR and volume was seen in Aβ+ participants (R2 = 0.55; P < .001) but not Aβ− (R2 = 0; P = .97) participants.

Conclusions and Relevance  Use of [18F]-AV-1451 has a potential for staging of the preclinical and clinical phases of AD. β-Amyloid interacts with hippocampal and cortical tauopathy to affect neurodegeneration. In the absence of Aβ, hippocampal tau deposition may be insufficient for the neurodegenerative process that leads to AD.

JAMA Neurology 2016

Phenotypic Similarities Between Late-Onset Autosomal Dominant and Sporadic Alzheimer Disease A Single-Family Case-Control Study

Importance  The amyloid hypothesis posits that disrupted β-amyloid homeostasis initiates the pathological process resulting in Alzheimer disease (AD). Autosomal dominant AD (ADAD) has an early symptomatic onset and is caused by single-gene mutations that result in overproduction of β-amyloid 42. To the extent that sporadic late-onset AD (LOAD) also results from dysregulated β-amyloid 42, the clinical phenotypes of ADAD and LOAD should be similar when controlling for the effects of age.

Objective  To use a family with late-onset ADAD caused by a presenilin 1 (PSEN1) gene mutation to mitigate the potential confound of age when comparing ADAD and LOAD.

Design, Setting, and Participants  This case-control study was conducted at the Knight Alzheimer Disease Research Center at Washington University, St Louis, Missouri, and other National Institutes of Aging–funded AD centers in the United States. Ten PSEN1 A79V mutation carriers from multiple generations of a family with late-onset ADAD and 12 noncarrier family members were followed up at the Knight Alzheimer Disease Research Center (1985-2015) and 1115 individuals with neuropathologically confirmed LOAD were included from the National Alzheimer Coordinating Center database (September 2005-December 2014). Data analysis was completed in January 2016, including Knight Alzheimer Disease Research Center patient data collected up until the end of 2015.

Main Outcomes and Measures  Planned comparison of clinical characteristics between cohorts, including age at symptom onset, associated symptoms and signs, rates of progression, and disease duration.

Results  Of the PSEN1 A79V carriers in the family with late-onset ADAD, 4 were female (57%); among those with LOAD, 529 were female (47%). Seven mutation carriers (70%) developed AD dementia, while 3 were yet asymptomatic in their seventh and eighth decades of life. No differences were observed between mutation carriers and individuals with LOAD concerning age at symptom onset (mutation carriers: mean, 75 years [range, 63-77 years] vs those with LOAD: mean, 74 years [range, 60-101 years]; P = .29), presenting symptoms (memory loss in 7 of 7 mutation carriers [100%] vs 958 of 1063 individuals with LOAD [90.1%]; P ≥ .99) and duration (mutation carriers: mean, 9.9 years [range, 2.3-12.8 years] vs those with LOAD: 9 years [range, 1-27 years]; P = .73), and rate of progression of dementia (median annualized change in Clinical Dementia Rating–Sum of Boxes score, mutation carriers: 1.2 [range, 0.1-3.3] vs those with LOAD: 1.9 [range, −3.5 to 11.9]; P = .73). Early emergence of comorbid hallucinations and delusions were observed in 57% of individuals with ADAD (4 of 7) vs 19% of individuals with LOAD (137 of 706) (P = .03). Three of 12 noncarriers (25%) from the PSEN1 A79V family are potential phenocopies as they also developed AD dementia (median age at onset, 76.0 years).

Conclusions and Relevance  In this family, the amyloidogenic PSEN1 A79V mutation recapitulates the clinical attributes of LOAD. Previously reported clinical phenotypic differences between individuals with ADAD and LOAD may reflect age- or mutation-dependent effects.

JAMA Neurology 2016

Genome-wide association analyses identify new risk variants and the genetic architecture of amyotrophic lateral sclerosis

To elucidate the genetic architecture of amyotrophic lateral sclerosis (ALS) and find associated loci, we assembled a custom imputation reference panel from whole-genome-sequenced patients with ALS and matched controls (n = 1,861). Through imputation and mixed-model association analysis in 12,577 cases and 23,475 controls, combined with 2,579 cases and 2,767 controls in an independent replication cohort, we fine-mapped a new risk locus on chromosome 21 and identifiedC21orf2 as a gene associated with ALS risk. In addition, we identified MOBP and SCFD1 as new associated risk loci. We established evidence of ALS being a complex genetic trait with a polygenic architecture. Furthermore, we estimated the SNP-based heritability at 8.5%, with a distinct and important role for low-frequency variants (frequency 1–10%). This study motivates the interrogation of larger samples with full genome coverage to identify rare causal variants that underpin ALS risk.

Neurology 2016

NEK1 variants confer susceptibility to amyotrophic lateral sclerosis

• To identify genetic factors contributing to amyotrophic lateral sclerosis (ALS), we conducted whole-exome analyses of 1,022 index familial ALS (FALS) cases and 7,315 controls. In a new screening strategy, we performed gene-burden analyses trained with established ALS genes and identified a significant association between loss-of-function (LOF) NEK1 variants and FALS risk. Independently, autozygosity mapping for an isolated community in the Netherlands identified aNEK1 p.Arg261His variant as a candidate risk factor. Replication analyses of sporadic ALS (SALS) cases and independent control cohorts confirmed significant disease association for both p.Arg261His (10,589 samples analyzed) and NEK1 LOF variants (3,362 samples analyzed). In total, we observed NEK1 risk variants in nearly 3% of ALS cases. NEK1 has been linked to several cellular functions, including cilia formation, DNA-damage response, microtubule stability, neuronal morphology and axonal polarity. Our results provide new and important insights into ALS etiopathogenesis and genetic etiology.

Nature Genetics 2016

Contemporary Issues Organ support after death by neurologic criteria Results of a survey of US neurologists

ABSTRACT

Objective: We sought to evaluate how neurologists approach situations in which families request prolonged organ support after declaration of death by neurologic criteria (DNC).

Methods: We surveyed 938 members of the American Academy of Neurology (AAN) who treat critically ill patients, including 50% who practice in states with accommodation exceptions (states that require religious or moral beliefs to be taken into consideration when declaring death or discontinuing organ support: California, Illinois, New Jersey, New York), and 50% who practice in nonaccommodation states.

Results: The survey was completed by 201/938 individuals (21% response rate), 96 of whom were from accommodation states and 105 of whom were from nonaccommodation states. Both groups reported encountering situations in which families requested continuation of organ support after DNC (48% from accommodation states and 46% from nonaccommodation states). In a hypothetical scenario where a request is made to continue organ support after DNC (outside of organ donation), 48% of respondents indicated they would continue support due to fear of litigation. In reply to an open-ended question, respondents requested that the AAN generate guidelines and advocate to codify laws regarding organ support after DNC, and to improve public and physician education on DNC.

Conclusions: Our findings suggest that it is relatively common for neurologists who treat critically ill patients to encounter families who object to discontinuation of organ support after DNC at some point during their career. It would be beneficial for physicians, families, and society to rely on clear medicolegal guidelines on management of this situation.

Neurology 2016

History of multiple sclerosis in 2 successive pregnancies A French and Italian cohort

ABSTRACT

Objective: To evaluate the risk of relapses during pregnancy and in the first 3 months after delivery in 2 successive pregnancies in a cohort of French and Italian women with multiple sclerosis (MS).

Methods: A total of 93 women were included if they had had 2 pregnancies followed prospectively after MS onset between January 1993 and 2013. The association of a relapse during pregnancy or the first postpartum trimester in pregnancy 1 and pregnancy 2 was evaluated by univariate logistic regression.

Results: A majority of women did not experience any exacerbation in the 3 months after delivery (31.2% and 23.7%, respectively, relapsed after pregnancy 1 and 2; p = 0.32). A total of 7.6% had a relapse after both pregnancies. The risk of relapse after pregnancy 2 was not associated with the number of relapses in the prepregnancy year (odds ratio [OR] 1.52 [0.57–4.05]) or during pregnancy (OR 1.57 [0.52–4.79]) or with the occurrence of a relapse after pregnancy 1 (OR 0.86 [0.29–2.50]).

Conclusions: Our work provides original data on the evolution of successive pregnancies in MS, showing a similar (and even lower) disease activity in the second pregnancy. There was no correlation of activity in successive pregnancies. Therefore, counseling of women with MS who consider having a second baby should be the same as for the first one.

Neurology 2016

The neurologist's role in supporting transition to adult health care A consensus statement

ABSTRACT

The child neurologist has a critical role in planning and coordinating the successful transition from the pediatric to adult health care system for youth with neurologic conditions. Leadership in appropriately planning a youth's transition and in care coordination among health care, educational, vocational, and community services providers may assist in preventing gaps in care, delayed entry into the adult care system, and/or health crises for their adolescent patients. Youth whose neurologic conditions result in cognitive or physical disability and their families may need additional support during this transition, given the legal and financial considerations that may be required. Eight common principles that define the child neurologist's role in a successful transition process have been outlined by a multidisciplinary panel convened by the Child Neurology Foundation are introduced and described. The authors of this consensus statement recognize the current paucity of evidence for successful transition models and outline areas for future consideration.

Neurology 2016

Seizures in dominantly inherited Alzheimer disease

ABSTRACT

Objective: To assess seizure frequency in a large French cohort of autosomal dominant early-onset Alzheimer disease (ADEOAD) and to determine possible correlations with causative mutations.

Methods: A national multicentric study was performed in patients with ADEOAD harboring a pathogenic mutation within PSEN1, PSEN2, APP, or a duplication of APP, and a minimal follow-up of 5 years. Clinical, EEG, and imaging data were systematically recorded.

Results: We included 132 patients from 77 families: 94 PSEN1 mutation carriers (MCs), 16 APP duplication carriers, 15 APP MCs, and 7 PSEN2 MCs. Seizure frequency was 47.7% after a mean follow-up of 8.4 years (range 5–25). After 5-year follow-up and using a Cox model analysis, the percentages of patients with seizures were respectively 19.1% (10.8%–26.7%) for PSEN1, 28.6% (0%–55.3%) for PSEN2, 31.2% (4.3%–50.6%) for APP duplications, and no patient for APP mutation. APP duplication carriers showed a significantly increased seizure risk compared to bothAPP MCs (hazard ratio [HR] = 5.55 [95% confidence interval 1.87–16.44]) and PSEN1 MCs (HR = 4.46 [2.11–9.44]). Among all PSEN1 mutations, those within the domains of protein hydrophilic I, transmembrane II (TM-II), TM-III, TM-IV, and TM-VII were associated with a significant increase in seizure frequency compared to other domains (HR = 4.53 [1.93–10.65], p = 0.0005).

Conclusions: Seizures are a common feature of ADEOAD. In this population, risk was significantly higher in theAPP duplication group than in all other groups. Within PSEN1, 5 specific domains were associated with a higher seizure risk indicating specific correlations between causative mutation and seizures.

Neurology 2016

Practice advisory: Recurrent stroke with patent foramen ovale (update of practice parameter) Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology

Objective: To update the 2004 American Academy of Neurology guideline for patients with stroke and patent foramen ovale (PFO) by addressing whether (1) percutaneous closure of PFO is superior to medical therapy alone and (2) anticoagulation is superior to antiplatelet therapy for the prevention of recurrent stroke.

Methods: Systematic review of the literature and structured formulation of recommendations.

Conclusions: Percutaneous PFO closure with the STARFlex device possibly does not provide a benefit in preventing stroke vs medical therapy alone (risk difference [RD] 0.13%, 95% confidence interval [CI] −2.2% to 2.0%). Percutaneous PFO closure with the AMPLATZER PFO Occluder possibly decreases the risk of recurrent stroke (RD −1.68%, 95% CI −3.18% to −0.19%), possibly increases the risk of new-onset atrial fibrillation (AF) (RD 1.64%, 95% CI 0.07%–3.2%), and is highly likely to be associated with a procedural complication risk of 3.4% (95% CI 2.3%–5%). There is insufficient evidence to determine the efficacy of anticoagulation compared with antiplatelet therapy in preventing recurrent stroke (RD 2%, 95% CI −21% to 25%).

Recommendations: Clinicians should not routinely offer percutaneous PFO closure to patients with cryptogenic ischemic stroke outside of a research setting (Level R). In rare circumstances, such as recurrent strokes despite adequate medical therapy with no other mechanism identified, clinicians may offer the AMPLATZER PFO Occluder if it is available (Level C). In the absence of another indication for anticoagulation, clinicians may routinely offer antiplatelet medications instead of anticoagulation to patients with cryptogenic stroke and PFO (Level C).

Neurology 2016

Anti-LGI1–associated cognitive impairment Presentation and long-term outcome

ABSTRACT

Objective: We investigated a series of patients with LGI1 antibody (Ab)–related cognitive deterioration to determine the clinical presentation, long-term outcome, and LGI1 Ab evolution.

Methods: We retrospectively analyzed the clinical information of 76 patients with LGI1 Ab–related cognitive deterioration. Presenting syndromes were classified as limbic encephalitis (LE), non-LE, or encephalopathy (normal MRI and no CSF pleocytosis). Frequency of relapses and clinical outcome were assessed in 48 patients with prolonged follow-up (median 39 months, range 18–200).

Results: Sixty-three patients (83%) developed LE, 3 (4%) non-LE, and 10 (13%) encephalopathy. All patients received steroids, IV immunoglobulins (Ig), or both. At 2 years, 17 (35%; 95% CI 21%–49%) fully recovered, 17 (35%) became functionally independent but not at baseline or were unable to return to work, 11 (23%) required assistance because of moderate or severe cognitive deficits, and 3 (6%) died. Predictors of bad outcome included no response to initial immunotherapy (odds ratio 23.0, 95% CI 2.4–215.6, p = 0.006) and clinical relapses (odds ratio 10.2, 95% CI 1.0–100.1, p = 0.047) that occurred in 13 patients (27%). In all patients, the LGI1 Abs were IgG4 and usually detectable in both serum and CSF (only CSF, 8%). Abs remained positive in serum of 4 of 16 patients with long-term follow-up; 3 of these 4 patients fully recovered and none showed class switch to IgG1.

Conclusions: Up to 13% of patients with LGI1 Abs develop cognitive impairment without criteria of encephalitis. After immunotherapy, only 35% of patients return to their baseline cognitive function. Serum LGI1 Abs may remain detectable after full clinical recovery.

Neurology 2016

Predictive value of ABCD2 and ABCD3-I scores in TIA and minor stroke in the stroke unit setting

ABSTRACT

Objective: It is not clear whether risk scores for early stroke recurrence after TIA that have been mainly established in outpatient and emergency department settings are valid on the background of highly specialized stroke unit care.

Methods: ABCD2 and ABCD3-I scores have been prospectively documented in a cohort of patients admitted to Austrian stroke units within 24 hours of symptom onset with TIA or minor stroke (NIH Stroke Scale score <4).

Results: A total of 5,237 TIA and minor stroke patients met inclusion criteria, with 3-month follow-up data available on 2,457. Early and 3-month stroke were observed in 2.4% and 4.2% of the study population. The probability of early stroke during the stroke unit stay (median 2 [interquartile range 1–3] days) steadily increased from 0% to 4.8% and 0% to 16.7% with increasing ABCD2 and ABCD3-I score points, respectively. On 3-month follow-up, stroke risk increased from 0% to 8.0% and 0% to 23.8% with increasing ABCD2 and ABCD3-I score points, respectively. Of the individual score components, age, blood pressure, and diabetes were not related to early or 3-month stroke, whereas clinical presentation (C), symptom duration (D), and cerebral as well as carotid imaging (I) were and accounted for the information provided by the full scores.

Conclusions: Standard ABCD2 and ABCD3-I scores are useful instruments to estimate the probability of early and 3-month stroke in TIA and minor stroke patients treated at specialized stroke units, with C, D, and I being the most important score components in this setting.

Neurology 2016

Effects of hormone therapy on brain structure A randomized controlled trial

ABSTRACT

Objective: To investigate the effects of hormone therapy on brain structure in a randomized, double-blinded, placebo-controlled trial in recently postmenopausal women.

Methods: Participants (aged 42–56 years, within 5–36 months past menopause) in the Kronos Early Estrogen Prevention Study were randomized to (1) 0.45 mg/d oral conjugated equine estrogens (CEE), (2) 50 μg/d transdermal 17β-estradiol, or (3) placebo pills and patch for 48 months. Oral progesterone (200 mg/d) was given to active treatment groups for 12 days each month. MRI and cognitive testing were performed in a subset of participants at baseline, and at 18, 36, and 48 months of randomization (n = 95). Changes in whole brain, ventricular, and white matter hyperintensity volumes, and in global cognitive function, were measured.

Results: Higher rates of ventricular expansion were observed in both the CEE and the 17β-estradiol groups compared to placebo; however, the difference was significant only in the CEE group (p = 0.01). Rates of ventricular expansion correlated with rates of decrease in brain volume (r = −0.58; p ≤ 0.001) and with rates of increase in white matter hyperintensity volume (r = 0.27; p = 0.01) after adjusting for age. The changes were not different between the CEE and 17β-estradiol groups for any of the MRI measures. The change in global cognitive function was not different across the groups.

Conclusions: Ventricular volumes increased to a greater extent in recently menopausal women who received CEE compared to placebo but without changes in cognitive performance. Because the sample size was small and the follow-up limited to 4 years, the findings should be interpreted with caution and need confirmation.

Classification of evidence: This study provides Class I evidence that brain ventricular volume increased to a greater extent in recently menopausal women who received oral CEE compared to placebo.

Neurology 2016

Cognitive and neurodevelopmental comorbidities in paediatric epilepsy

Cognitive and behavioural comorbidities are often seen in children with epilepsy, and are more common and severe in refractory epilepsy. These comorbidities are associated with worse quality of life, increased behavioural and language problems and worse social skills, all of which adversely affect long-term psychosocial functioning. To enable early intervention and therapy, children and teens with epilepsy should be periodically screened for cognitive comorbidities. The location of the epileptic focus can, to a certain degree, predict the type(s) of comorbidity; however, the spectrum of disability is often broad, presumably because focal perturbations can cause network dysfunction. Comorbidities often result from underlying structural or functional pathology that has led to seizures. In selected cases, therapy targeting the underlying cause, such as the ketogenic diet for GLUT1 deficiency syndromes, may be remarkably effective in ameliorating both seizures and cognitive concerns. In many cases, however, cognitive impairment persists despite seizure control. In epileptic encephalopathies, frequent seizures and/or interictal epileptiform abnormalities exacerbate neurocognitive dysfunction, owing to synaptic reorganization or impaired neurogenesis, or to other effects on developing neural circuits, and prompt initiation of effective antiepileptic therapy is essential to limit cognitive comorbidities.

Neurology 2016